Find the formula of `A`
`ZnS + O_(2) rarr (A) + SO_(2)`.

Options

A. `ZnCO_(3)`
B. `ZnO`
C. `ZnSO_(4)`
D. `ZnCO_(3).3Zn(OH)_(2)`

Explanation

To find the formula of compound `A` in the reaction:

\[ \text{ZnS} + \text{O}_2 \rightarrow (A) + \text{SO}_2 \]

we can follow these steps:

### Step 1: Identify the reactants
The reactants in the equation are zinc sulfide (ZnS) and oxygen (O₂).

### Step 2: Understand the process
The process described is roasting, which involves heating the ore (ZnS) in the presence of oxygen. This typically leads to the oxidation of the sulfide.

### Step 3: Determine the products
When zinc sulfide is roasted in the presence of oxygen, it undergoes oxidation. The sulfur in ZnS is oxidized to sulfur dioxide (SO₂), and zinc is converted to zinc oxide (ZnO).

### Step 4: Write the balanced equation
The balanced chemical equation for the roasting of zinc sulfide can be written as:

\[ \text{2 ZnS} + \text{3 O}_2 \rightarrow \text{2 ZnO} + \text{2 SO}_2 \]

From this equation, we can see that the product `A` is zinc oxide (ZnO).

### Step 5: Conclusion
Thus, the formula of `A` is:

\[ A = \text{ZnO} \]

### Final Answer
The formula of `A` is ZnO.

---